Surgical retractor

ABSTRACT

A surgical retractor is provided including a handle portion, a tubular portion extending from the handle portion, and a collapsible retractor assembly connected to a distal end of the tubular portion. The handle portion includes an actuating structure for manipulating the collapsible retractor assembly through the tubular portion. The retractor assembly includes a plurality of retractor blades, a camming assembly connected to the retractor blades and structure for connecting the retractor blades to the actuating structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in part of applicant's co-pendingapplication Ser. No. 07/740,443, which application was filed on Aug. 5,1991, now U.S. Pat. No. 5,199,419.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to surgical instrumentation and, moreparticularly, to a surgical retractor having deployable blades for usewith endoscopic or laparoscopic devices in performing examinations orsurgical procedures within body cavities.

2. Description of Related Art

Most endoscopic or laparoscopic procedures are characterized by theprovision of an elongated cannula structure having a relatively thindiameter with a proximal and distal end. The distal end is passedthrough the surrounding tissue into the body cavity wherein the surgicalprocedure or examination is to be effected, thus providing a conduit forthe insertion of surgical instrumentation. A plurality of cannulastructures may be used to allow operation of a variety of instrumentssimultaneously during a given procedure.

In conventional surgical procedures the function of holding tissue andorgans in a given location to facilitate access and viewing is typicallyaccomplished by a retractor. This instrumentation is ordinarily in theform of a broad paddle structure or multiple fingers attached to ahandle. See, for example, U.S. Pat. No. 3,467,079 (James). Thisstructure, however, is not usable in endoscopic procedures because theretractor is too large to be insertable through the cannula structureinto the operative body cavity.

Collapsible intralumen expanders or retractors have taken the form ofradial fingers which are activatable to extend relative to each otherupon entering the body cavity. See, for example, U.S. Pat. Nos.4,654,028 (Suma), 4,459,978 (Kotsanis). Dilators of this type are alsoknown. See, for example, U.S. Pat. Nos. 1,328,624 (Graham) and 972,983(Arthur). In each case, once the retractive or dilatory function iscompleted, the fingers are compressed and withdrawn. Another collapsibleretractor structure includes a pair of collapsible fingers joined by aweb of resilient material which, upon insertion into the cannulastructure, can expand to form a retractive structure. See, for example,U.S. Pat. No. 4,190,042 (Sinnreich).

Greatly improved retractor structure has been developed and is describedin commonly assigned co-pending patent application Ser. No. 07/634,482filed Dec. 27, 1990. That structure shows a plurality of interleavedretractor blades mounted in a tubular housing. The blades are movablebetween a closed position and an open position to facilitate ease ofinsertion and deployment through a cannula. Other surgical apparatushaving deployable interleaved retractor blades have been described inSoviet references. See, for example, SU 736-949 (MOME) which describesan instrument having an elongated housing with a plurality of bladesoperative at one end by means of a manipulator at the opposed end, andSU 1360-708-A (MEDI) which describes an instrument having a plurality ofinterleaved blades which cannot be manipulated at a distance and thus isunsuited for performing endoscopic or laparoscopic procedures.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a surgical retractorwhich overcomes the drawbacks and deficiencies associated with prior artretractors.

Another object of the present invention is to provide a surgicalretractor adapted for use in endoscopic and laparoscopic procedures.

A further object of the present invention is to provide a surgicalretractor which is easily deployable within a body cavity to provide aretractive function therein.

The present invention provides a novel surgical retractor which hasadvantageous specific applications in endoscopic and laparoscopicsurgical procedures and examinations. The surgical retractor includes ahandle assembly, a housing means and a collapsible retractor assemblyconnected to a distal end of the housing means.

The handle assembly includes a handle in cooperation with an actuatingstructure for manipulating the collapsible retractor assembly throughthe housing means in response to relative motion between the actuatingstructure and the handle. The handle assembly may be configured in avariety of forms including palm grips, pistol grips, axial grips, ringgrips, etc.

The housing means, in its most basic embodiment, comprises an elongatedtubular structure having an inner tube axially disposed within an outertube. The outer tube is typically fixed in the stationary handle withthe inner tube passing through the outer tube and connected to theactuating structure. The inverse of this configuration, i.e., the innertube fixed to the stationary handle with the outer tube connected to theactuating structure, is equally useful. Where independent rotation ofthe tubular housing is desired, the outer tube or inner tube may berotatably attached to the stationary handle.

A retractor assembly is attached to the distal end of the housing meansand includes a reciprocal yoke assembly interconnected with a pluralityof collapsible interleaved retractor blades. One element of the yokeassembly is usually maintained stationary while the other is allowed toreciprocate axially to deploy the interleaved retractor blades into afan configuration.

In alternate embodiments an enclosure tube is provided surrounding theinner and outer tubes. In order to deploy the interleaved retractorblades, the blades are first moved out of the distal end of theenclosure tube.

In preferred embodiments of the subject invention the retractor assemblymay include a plurality of retractor blades each having an elongatedplanar body section and a distal head section depending angularly fromthe plane of the body section at an angle of between 0° and 90° relativeto the plane thereof. Preferably, the distal head section depends fromthe body section at an angle of approximately 45°.

The retractor assembly includes a center retractor blade, an upperretractor blade, and a lower retractor blade, each blade being pivotallyconnected to one another by a pin. Camming means are operativelyconnected to the upper and lower retractor blades and includecorresponding upper and lower cam beams which may be fixedly mountedwithin the tubular portion of the instrument adjacent the distal endthereof. The upper cam beam includes an upper camming slot definedtherein, while the lower cam beam has a corresponding lower camming slotdefined therein. The slots are symmetrically disposed relative to oneanother for facilitating a fan-like deployment of the retractorassembly. Camming pins are associated with the upper and lower camblades for movement relative to the camming slots. A rod member isprovided for operatively connecting the center retractor blade to thehandle assembly.

In preferred embodiments of the invention, the handle assembly includesmanipulating means comprising a rotatable driving screw mounted relativeto the handle assembly and an axially moveable sleeve member which isthreadably associated with the driving screw. Rotation of the drivingscrew causes corresponding axial movements of the sleeve member.Preferably, the sleeve member is connected to the center retractor bladeby the rod member so that movements of the sleeve member will causemanipulation of the retractor assembly. Alternatively, the manipulatingmeans may comprise a driving screw mounted for axial translationrelative to the handle assembly in response to rotation of a sleevedknob member.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing objects and other features of the invention will becomemore readily apparent and may be understood by referring to thefollowing detailed description of preferred embodiments, taken inconjunction with the accompanying drawings forming a part hereof.

FIG. 1 is a perspective view of a preferred embodiment of the presentinvention.

FIG. 2 is a side view in cross section of a preferred embodiment of thepresent invention with the retractor blades deployed in a fanconfiguration.

FIG. 3 is a side view in cross section of a preferred embodiment of thepresent invention with the retractor blades folded and enclosed by anenclosure tube.

FIG. 4 is a side view of the retractor blades and the reciprocal yokeassembly for the surgical retractor of FIGS. 1-3.

FIG. 5 is an exploded perspective view of a preferred embodiment of thepresent invention.

FIG. 6 is a top view of the pivot yoke assembly for a preferredembodiment of the present invention.

FIG. 7 is a side view of the pivot yoke assembly taken through line 7--7of FIG. 6.

FIG. 8 is an end view of the pivot yoke assembly taken through line 8--8of FIG. 7.

FIG. 9 is a top view of the slide yoke assembly for a preferredembodiment of the present invention.

FIG. 10 is a side view of the slide yoke assembly taken through line10--10 of FIG. 9.

FIG. 11 is an end view of the slide yoke assembly taken through line11--11 of FIG. 10.

FIG. 12 is a top view of a handle in accordance with a preferredembodiment of the present invention.

FIG. 13 is a side view of a handle taken along line 13--13 of FIG. 12.

FIG. 14 is an unfolded end view of a proximal end of the handle of FIG.12 incorporating progressive stops in the camming surfaces.

FIG. 15 is a side view in cross section of the rotation knob.

FIG. 16 is a side view in cross section of a surgical retractor inaccordance with a preferred embodiment of the present invention.

FIG. 17 is a top view of a handle in accordance with the surgicalretractor of FIG. 16.

FIG. 18 is a side view of a handle taken along line 18--18 of FIG. 17.

FIG. 19 is a side view in cross section of a handle assembly inaccordance with a preferred embodiment of the present invention.

FIG. 20 is a side view of a barrel cam structure for use in the handleassembly of FIG. 19.

FIG. 21 is an end view of the barrel cam of FIG. 20 taken along line 2121.

FIG. 22 is a side view of a barrel cam structure having progressivestops formed into the camming surfaces.

FIG. 23 is a side view of a pivot yoke in accordance with a preferredembodiment of the present invention.

FIG. 24 is a top view of a pivot yoke taken along line 24--24 of FIG.23.

FIG. 25 is a side view in partial cross section of a preferredembodiment of a closed surgical retractor in accordance with the presentinvention.

FIG. 26 is a side view in partial cross section of the surgicalretractor of FIG. 25 with the retractor blades in the deployed position.

FIGS. 27-29 show preferred embodiments of retractor blades for use withthe present invention.

FIG. 30 is a side view in partial cross section of a preferredembodiment of an open surgical retractor in accordance with the presentinvention.

FIG. 31 is a side view of the retractor assembly of the surgicalretractor of FIG. 30 in the closed position.

FIG. 32 is a top view of the retractor assembly having a blunt end.

FIG. 33 is a side view of the retractor assembly of FIG. 32 through line33--33.

FIG. 34 is a side view of the retractor assembly having a hollow end.

FIG. 35 is a top view of the retractor assembly of FIG. 34 taken throughline 35--35.

FIG. 36 is a perspective view of a preferred embodiment of the retractorassembly in the closed position.

FIG. 37 is a perspective view of the retractor assembly of FIG. 36 inthe deployed position.

FIG. 38 is a perspective view of a preferred embodiment of the retractorassembly in the closed position.

FIG. 39 is a perspective view of the retractor assembly of FIG. 38 inthe deployed position.

FIG. 40 is a perspective view of a preferred embodiment of the retractorassembly in the closed position.

FIG. 41 is a perspective view of the retractor assembly of FIG. 40 inthe deployed position.

FIG. 42 is a perspective view of another preferred embodiment of thesurgical retractor in accordance with the subject invention.

FIG. 43 is an exploded perspective view of the surgical retractor ofFIG. 42.

FIG. 43a is an enlarged exploded perspective view of the retractorassembly of FIG. 43.

FIG. 44 is a perspective view in partial cross-section of the surgicalretractor of FIG. 42, with the retractor assembly thereof in a closedposition.

FIG. 45 is a perspective view in partial cross-section of the surgicalretractor of FIG. 42, with the retractor assembly thereof in a partiallydeployed position.

FIG. 46 is a perspective view in partial cross-section of the surgicalretractor of FIG. 42, with the retractor assembly thereof in a fullydeployed position.

FIG. 47 is an enlarged exploded perspective view of a handle assemblyfor use with the surgical retractor of FIG. 42.

FIG. 48 is an exploded perspective view of another preferred embodimentof the surgical retractor in accordance with the subject invention.

FIG. 49 is a perspective view in partial cross-section of the surgicalretractor of FIG. 48, with the retractor assembly thereof in a closedposition.

FIG. 50 is a perspective view in partial cross-section of the surgicalretractor of FIG. 48, with the retractor assembly thereof in a partiallydeployed position.

FIG. 51 is a perspective view in partial cross-section of the surgicalretractor of FIG. 48, with the retractor assembly thereof in a fullydeployed position.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now in specific detail to the drawings, in which likereference numbers identify similar or identical elements, FIGS. 1-3illustrate a preferred embodiment of a surgical retractor, showngenerally at 60. The retractor 60 can be broken down into a retractorassembly 62, elongated tubular housing means 64 and handle means 66. Theembodiment of FIGS. 1-3 is adapted for and particularly useful inendoscopic or laparoscopic procedures wherein at least an endoscopicportion of the surgical retractor 60 is inserted into the operative sitethrough a cannula (not shown).

The retractor assembly 62 generally comprises a plurality of interleavedelongated blades 68 disposed in stacked relation and pivotallydeployable about a proximal end to form an interleaved fan configuration(FIG. 2). This fan configuration can be readily adapted to differentshapes and uses by either varying the number or size of the blades 68 ortheir respective angles of deployment. In the closed stacked position,the blades 68 fold in upon each other in axial alignment (FIGS. 3 and4). In the embodiment of FIGS. 1-3, the retractor assembly 62 iscontained within an enclosure tube 70 prior to deployment (FIG. 3) aswill be discussed in greater detail below.

Referring to FIGS. 5-11, each of the blades (collectively referred to as68) of the retractor assembly is provided with a fixed pivot hole 72 ina proximal end thereof. A camming slot 74 is located distal to the pivothole 72 and is formed at predetermined angles to effect properdeployment of the retractor assembly 62. In the embodiment of FIGS. 1-5,for example, center blade 76 is provided with an axially aligned cammingslot to maintain the blade in a fixed axial orientation. The bladespositioned adjacent center blade 76, i.e. blades 78, 80, cam outward inopposing directions to a predetermined angle with respect to thelongitudinal plane of the center blade 76. Similarly, the outward mostblades, i.e. 82, 84, have camming slots which cause the blades to movein opposing directions to a predetermined angle greater than that ofblades 78 and 80 so as to form a fan configuration which deploys outwardrespectively from the center blade 76.

Blades 68 are interconnected by a unique reciprocal yoke assembly 86(FIGS. 5-11) including a pivot yoke 88 (FIGS. 6-8) and a slide yoke 90(FIGS. 9-11). Referring to FIGS. 5-8, pivot yoke 88 includes a pair ofparallel axially extending arms 92 containing a transverse bore 94 in adistal end thereof. Pin 96 extends through transverse bore 94 and eachof the fixed pivot holes 72 formed in the proximal ends of blades 68.Thus blades 68 are free to pivot about pin 96 in pivot yoke 88.

Slide yoke 90 includes a pair of axially extending parallel arms 98,each having a transverse bore 100 formed in a distal end thereof. Eachparallel arm 98 is further provided with a longitudinal channel 102adapted and configured to receive parallel arms 92 of the pivot yoke 88therein. Pin 104 extends through transverse bore 100 and camming slots74 in blades 68. As the pivot yoke 88 and slide yoke 90 movereciprocally relative to one another in channel 102, the movement of pin104 in camming slots 74 effects the deployment and closure of blades 68.

Referring to FIGS. 1-3 and 5, elongated tubular housing means 64includes a center rod 106 disposed within a guide tube 108. In thepresent embodiment, an enclosure tube 70 serves to at least partiallyenclose the combined center rod 106 and guide tube 108. Slide yoke 90 isprovided with an axial bore 110 for fixedly receiving a distal end ofcenter rod 106. Pivot yoke 88 has an axial bore 112 aligned with bore110 to permit center rod 106 to reciprocally move slide yoke 90 withrespect to pivot yoke 88. Pivot yoke 88 is fixed to the distal end ofguide tube 108 (FIG. 5) and serves to pivotally hold blades 68 in place.

Referring now to FIGS. 5 and 12-15, handle means 66 comprises an axiallyaligned, substantially cylindrical housing 110 having a central bore 112extending from a proximal end 114 to a distal end 116. At the proximalend, a helical camming surface 118 is provided with integral stoppingtabs 120. See FIGS. 12-14. Where desired, intermediate grooves 122 maybe formed in the helical camming surface 118 to provide sequential stopsin the deployment of the retractor assembly 62. See FIG. 14.

Deployment knob 124 (FIG. 15) interfits into the distal end 116 ofcylindrical housing 110 with the helical camming surface 118 at leastpartially contained in annular channel 126. A center projection 128contains a cavity 130 for receiving and securing a proximal end 132 ofcenter rod 106. Capping element 134 attaches to end 132 and is adaptedto be securely retained within cavity 130 while allowing deployment knob124 to rotate. A transverse camming pin 125 is mounted in deploymentknob 124 with a portion of the pin 125 extending into annular channel126 to engage helical camming surface 118.

A clasp knob 136 is fixed to outer bushing 138 and serves to retract andextend enclosure tube 70. Both clasp knob 136 and outer bushing 138 arefixed to enclosure tube 70 and move axially reciprocally therewith tocover and uncover the retractor assembly 62. Clasp knob 136 is providedwith a transversely flexible locking member 140 having a hooked lockingtab 142 attached thereto. This locking tab 142 is adapted to betransversely cammed by flange 144 in housing 110 and to abut and engagean inner surface 146 of flange 144. See FIGS. 2, 3 and 5.

Outer bushing 138 telescopically engages inner bushing 148 and isaxially movable along the inner bushing 148. A cylindrical cavity 150 isformed in housing 110 to accommodate both the inner bushing 148 and theouter bushing 138. Inner bushing 148 is provided with a flange 152 at aproximal end, which flange 152 travels axially in cavity 154 in aproximal end of housing 110. An extension spring 156 is disposed incavity 154 between flange 152 and center projection 128 of deploymentknob 124. This extension spring 156 serves to apply an axial distalforce on the flange 152 of inner bushing 148 which force is transmittedthrough the flange to center projection 128 of deployment knob 124. Thisaxial distal force maintains pressure on camming pin 125 against helicalcam 118. A set screw 158 is provided in housing 110 to limit travel offlange 152 in cavity 154.

To deploy the retractor assembly 62 of this embodiment of the presentinvention from the closed position (FIG. 3), clasp knob 136 is movedproximally until hooked locking tab 142 just abuts flange 144. At thispoint, the proximal end of outer bushing 138 abuts flange 152 of innerbushing 148 and the hooked locking tab 142 of transversely flexiblelocking member 140 engages inner surface 146 of flange 144 thus lockingenclosure tube 70 in the retracted position. See FIG. 2.

Thereafter, deployment knob 124 is rotated, driving transverse cammingpin 125 along helical camming surface 118 formed in the proximal end 114of cylindrical housing 110. This action moves deployment knob 124proximally with respect to cylindrical housing 110 and drawing centerrod 106 in a proximal direction with respect to guide tube 108. Ascenter rod 106 moves proximally, pivot yoke 86 retracts in channels 102of slide yoke 90 causing pin 96 to cam in camming slots 74 of retractorblades 68 which, simultaneously pivot in a predetermined configurationabout pin 104 in slide yoke 90.

Closure of the retractor assembly 62 is accomplished simply by rotatingdeployment knob 124 in the opposite direction to bring blades 68 into astacked interleaved position. Transversely flexible locking member 140is depressed to disengage hooked locking tab 142 from the inner surface146 of flange 144. Thereafter, transversely flexible locking tab 142 ismoved distally until enclosure tube 70 covers at least a portion of theclosed retractor assembly 62. See FIG. 3.

Referring to FIGS. 16-18, a variation of the embodiment of the surgicalretractor of FIGS. 1-16 is shown. The surgical retractor, showngenerally at 160, includes the same basic subgroups discussed aboveincluding a retractor assembly 62, an elongated tubular housing means 64and a handle means 66.

The retractor assembly 62 and the elongated tubular housing means 64 aresubstantially similar in construction and operation as those of thesurgical retractor 60 discussed above. Handle means 66, however, differsin some structural aspects. A cylindrical housing 162 having a proximalend 164 and a distal end 166 with a central bore 168 therethrough isprovided. The bore 168 is restricted in size near distal end 166 ofhousing 162 and is substantially open at the proximal end 164. See FIG.18. A pair of annular flanges 170, 172 are axially sequentially disposedin the distal end 166 of housing 162, each such flange defining arespective inner surface 174, 176. Inner and outer bushings, 148 and 138respectively, are configured and operate substantially the same as thosedescribed above with respect to FIGS. 1-15. Center rod 106, however, isfixed to disk 178 which is anchored in the opening 180 in the proximalend 164 of housing 162 by means of set screws 180, 182. A compressionspring 156 is disposed between flange 152 of inner bushing 148 and disk178 and, when compressed, imparts a distal axial force to move claspknob 136 and the attached enclosure tube 70 distally. Flange 152 islimited in axial movement by pin 184 extending transversely from theouter edge of flange 152 into axial slot 186.

To deploy the retractor assembly 62 of this surgical retractor 160 fromthe closed position, clasp knob 136 is moved in a proximal directionexposing retractor assembly 62. Hooked locking tab 142 of transverselyflexible locking member 140 engages the inner surface 174 of distal mostannular flange 170 effectively locking enclosure tube 70 in its mostproximal position. Continued proximal motion of clasp knob 136 causesouter bushing 138 to engage inner bushing 148 and move inner bushingproximally with respect to center rod 106. This motion causes theretractor assembly 62 to deploy in a manner substantially the same asthat set forth above with respect to the embodiment of FIGS. 1-15. Atits proximal most position, the hooked locking tab 142 of transverselyflexible locking member 140 engages the inner surface 176 of proximalmost annular flange 172 thus locking the blades 68 in a deployed fanconfiguration.

Referring now to FIGS. 19-22, further variation of the handle means ofthe preferred embodiment of FIGS. 1-15 is shown. The handle means 188includes a cylindrical housing 190 having a proximal end 192 and adistal end 194 with a central bore 196 therethrough. A clasp knob 136attached to an outer bushing 138 and an enclosure tube 70 serves toeffect proximal and distal motion of the enclosure tube in substantiallythe same way as that described above. An inner bushing 148 connects toguide tube 108 and has an axial bore 198 disposed therein to allowpassage of center rod 106. Movable block 200 engages and holds aproximal end of center rod 106 for limited axial reciprocal motion. Atransverse camming pin 202 extends through movable block 200 and travelsaxially in slots 204, 206 formed in cylindrical housing 190.

Deployment of the retractor assembly 62 is accomplished by means of afan adjust collar 208 having a flange 2 10 in a distal end and a barrelcam slot 212 in a proximal end interconnected by a drive tube 214.Barrel cam slot 212 may either provide a smooth progression (FIG. 20) ormay utilize intermediate grooves 216 (FIGS. 22) to give intermediatestops as the blades 68 deploy. A compression spring 218 is disposedbetween inner bushing 148 and movable block 200 in order to preload thesystem and to assist in distal movement of enclosure tube 70.

In operation, hooked locking tab 142 of transversely flexible lockingmember 140 is moved proximally until tab 142 engages and locks in placebehind flange 210 in fan adjust collar 208. In this position, enclosuretube 70 is located at its proximal most position exposing the retractorassembly 62. Fan adjust collar 208 is then rotated relative tocylindrical housing 190 causing transverse camming pin 202 to be drivenaxially distally by barrel cam slot 2 12 in slots 204, 206. Thisrelative axial distal motion deploys blades 68 into a fan configuration.

To close the retractor, fan adjust collar 208 is rotated in the oppositedirection to move the blades 68 together. Transversely flexible lockingmember 140 is depressed to disengage hooked locking tab 142 from flange210. Compression spring 218 assists in the distal movement of enclosuretube 70. Clasp knob is then moved distally until enclosure tube 70 is atits distal most position enclosing at least a portion of retractorassembly 62.

FIGS. 25-29 illustrate a surgical retractor, indicated generally at 220,utilizing a pistol grip-type handle means 222 and an abbreviatedretractor assembly 224. The handle means 222 includes a stationaryhousing 226 with a depending finger grip 228 integrally formedtherewith, and a pivotal arm 230 having a depending finger grip 232 on aproximal end thereof and a rack 234 formed on a distal end. Pivotal arm230 attaches to stationary housing 226 by means of a pivot pin 236. Boththe depending finger grip 228 of the stationary housing 226 and thedepending finger grip 232 of pivotal arm 230 have provided thereoncomplementary inward facing racks, 238,240 respectively, whose teeth 242progressively interlock to hold pivot arm 230 at a predetermined angularorientation with respect to stationary housing 226.

A longitudinal cavity 244 is provided in an upper portion of stationaryhousing 226 to accommodate the reciprocal longitudinal motion of boltassembly 246. This bolt assembly comprises a proximally mountedcylindrical pinion 248 followed distally by a mounting block 250 forfixedly holding center rod 252. A guide tube mounting block 254 isattached distally to mounting block 250 and includes a bolt handle 256fixed to the guide tube mounting block 254 which handle 256 is guided inaxial movement by slot 258 formed in stationary housing 226. Guide tubemounting block 254 is provided with an axial bore 260 therethrough toallow center rod 252 to be driven distally by the interaction of rack234 and cylindrical pinion 248 as described below.

An endoscopic enclosure tube 262 is fixed to stationary housing 226 andserves to enclose and protect the retractor assembly 224 when it isclosed and retracted. Guide tube 264 extends from guide tube mountingblock 254, through enclosure tube 262 to attach to a pivot yoke assembly90 as described above. Center rod 252 extends from mounting block 250,through axial bore 260 and guide tube 264 to attach to slide yokeassembly 88. A rotation knob 265 is rotatably mounted in stationaryhousing 226 and engages guide tube 264 so as to allow direct rotation ofthe retractor assembly 224.

The abbreviated retractor assembly 224 operates in a manner similar tothat described above with respect to retractor assembly 62, and includesan axial blade 266 (FIG. 29) connected at a proximal end to center rod252. A pair of angularly deployable blades 268, 270 with serratedlongitudinal side edges 272, 274 cooperate with axial blade 266 toassist in the retractor function. Axial blade 266 is texturized alongits flat surfaces 276 to assist in gripping and retracting tissue.Blades 268, 270 are provided with a pivot hole 278 in a proximal end anda camming slot 280 located distally to pivot hole 278. A pivot pin 282mounted in pivot yoke assembly 88 passes through pivot holes 278 andacts as a pivot point for blades 268 and 270. A camming pin 284 istransversely mounted in axial blade 266 (FIG. 29) and rides in cammingslots 280 to angularly deploy blades 268 and 270 as the axial blade 266is reciprocally moved with respect to pivot yoke assembly 88. An axialslot 283 is provided in axial blade 266 proximal to transverse cammingpin 284. This slot 283 allows axial blade 266 to move reciprocally withrespect to pivot pin 282. A compression spring 286 is disposed betweenthe distal end of axial blade 266 and pivot yoke assembly 88 and iscompressed upon deployment of the retractor assembly 224. Thiscompressed force assists in the closure of the blades 268, 270 when theforce is released.

To operate surgical retractor 220, bolt handle 256 is moved distally inslot 258 thus moving bolt assembly 246 forward. This action moves theabbreviated retractor assembly 224 out of the distal end of enclosuretube 262 and concurrently engages cylindrical pinion 248 with rack 234.See. FIG. 26. Finger grips 228, 232 are approximated about pivot pin 236causing rack 234 to drive cylindrical pinion 248 in a proximal directiondrawing axial blade 266 proximally relative to pivot yoke assembly 88.Blades 268 and 270 are thus deployed by the motion of cam pin 284 incamming slots 280. Complementary racks 238 and 240 interlock to maintainthe blades in a deployed attitude.

To close the retractor 220, teeth 242 of racks 238, 240 are disengagedand, with the assistance of compression spring 286, finger grips 228,232 are moved apart until rack 234 disengages from cylindrical pinion248. Bolt assembly 246 can then be drawn proximally to retract theclosed blade assembly into enclosure tube 262.

Referring to FIGS. 23, 24 and 30-40 and specifically to FIG. 30, asurgical retractor 288 is shown in accordance with a simplifiedembodiment of the present invention. The surgical retractor 288 includesa retractor assembly 290 having a housing member 292 with a bladestorage cavity 294 formed in a distal end. A transverse bore 296 isformed in a proximal end of housing member 292 and serves to retainpivot pin 298 therein. Referring to FIGS. 23 and 24, a slide yokeassembly 300 interconnects with a distal end of center rod 106 andincludes a pair of axial legs 302 with an aligned transverse bore 304and an aligned, axial slot 306 formed therein. A moving pin 308 isdisposed in transverse bore 304 and axial slot 306 serves to enclosepivot pin 298 and permit axial reciprocal motion of the slide yokeassembly 300 relative to pivot pin 298.

A blade assembly 310 is disposed in retractor assembly 290 and includesa pair of inner blades 312 and a pair of outer blades 314. Each of saidblades 312, 314 include a pivot bore 316 formed in a proximal end and acam slot 318 positioned distal to the pivot bore 316. In the embodimentof FIG. 30, the outer edges of blades 312,314 are provided withserrations 320 to assist in the retractor function. Other modificationsincluding texturized coatings, abrasive surfaces, etc. could also beutilized and are within the scope of the present invention.

Blades 312, 314 are retained in blade storage cavity 294 with pivot pin298 positioned in pivot bores 316. Moving pin 308 of slide yoke assembly300 is disposed in cam slots 318 such that reciprocal axial motion ofslide yoke assembly 300 relative to housing member 294 causes moving pin308 to move in cam slots 318 to either deploy or retract blades 312, 314about pivot pin 298.

An elongated tubular housing assembly 322 is connected to retractorassembly 290 and includes a center rod 106 and a guide tube 108. Centerrod 106 extends through guide tube 108 and is connected at a distal endto slide yoke assembly 300 and at a proximal end to handle means 324.Guide tube 108 is attached at a distal end to housing member 292 and ata proximal end to handle means 324. In this embodiment of surgicalretractor 288, guide rod 106 is axially fixed in handle means 324.Center rod 106 is adapted for axial reciprocal motion within guide tube108.

Handle means 324 includes a stationary handle 326 and a pivoting handle328. Finger loops 330, 332 are provided on the lower ends of handles326, respectively. Where desired, racks 329, 33 1 may be provided withthe handles 326, 328 as discussed above in order to lock the retractorassembly 290 at a predetermined degree of deployment.

Pivoting handle 328 is pivotally mounted to stationary handle 326 bypivot pin 334. A pivot bushing 336, comprising a pair of disks 338 eachhaving connecting means for interengaging the disks 338 with each other,captures a proximal end of center rod 106 to control axial motionthereof. This pivot bushing 336 retains the proximal end of center rod106 while permitting the rod 106 to freely rotate therein and maintainthe rod 106 in axial alignment with guide tube 108 throughout the entirerange of motion of pivoting handle 328.

In preferred embodiments, as shown in FIG. 30, the retractor assembly290 and the elongated tubular housing assembly 322 are axially rotatableby rotation knob 340 mounted in stationary handle 326. This rotationknob 340 engages bushing 342 attached to guide tube 108. Rotation knob340 is preferably knurled or provided with ridges to allow for easymanipulation by the user's thumb or fingers. Similarly, bushing 342 maybe provided with angular faces of polygonal cross-section cooperatingwith corresponding faces formed in the stationary handle 326 so as toprovide predetermined rotational stops wherein the retractor assembly290 is maintained at a given angular orientation relative to the handlemeans 324.

To deploy the retractor assembly 290 of surgical retractor 288, pivotinghandle 328 is moved from an initial position (shown in phantom in FIG.30) to a final position wherein pivot bushing 336 is moved distally intoclose approximation with stationary handle 326. This motion drivescenter rod 106 distally through guide tube 108 thereby driving slideyoke assembly 300 with moving pin 308 through cam slots 318 in blades312, 314. Depending upon the degree of distal movement of center rod 106relative to guide tube 108, blades 312, 314 are caused to deploy aboutpivot pin 298 into a fan configuration. See FIG. 30. To close theretractor assembly 290, handles 326 and 328 are approximated causingpivot bushing 336 to move proximally with respect to pivot pin 334. Thisproximal movement draws center rod 106 and thus moving pin 308 in aproximal direction moving blades 312, 314 into a stacked interleavedconfiguration in blade storage cavity 294.

Referring now to FIGS. 31-41, there is shown a wide variety of housingmember configurations for retractor assemblies. In FIG. 31, housingmember 292 includes a streamlined removable tip portion 346 attached ata distal end to protect blade storage cavity 294.

FIGS. 32 and 33 show a housing member 344 integrally formed with guidetube 108 wherein the distal ends are crimped over to form a bluntrectangular end 348 distal to blade storage cavity 294. A transversebore 304 is formed in housing member 344 to receive stationary pivot pin298. Aperture 350 serves as an attachment point for bushing 342 topermit rotation of guide tube 108 by rotation knob 340. Similarly, FIGS.34 and 35 show a housing 344 integrally formed with guide tube 108 witha distal end 352 formed in a blunt cylindrical shape. A transverse bore304 is formed proximal to blade storage cavity 294 and an aperture 350interconnects guide tube 108 with bushing 342.

FIGS. 36 and 37 show a closed end housing member 354 having a roundeddistal portion 356 with a rectangular cross-section. Proximal to roundeddistal portion 356, upper and lower surfaces 358, 360 of housing member354 are substantially flattened and then ramp out to conform in diameterand cross-section with guide tube 108. A transverse bore 304 is formedin housing member 354 proximal to blade storage cavity 294 to receivepivot pin 298 therein. Blades 362 pivot about pivot pin 298 between aclosed position (FIG. 36) and a deployed position (FIG. 36) as describedabove.

FIGS. 38 and 39 show a streamlined closed end housing member 364 havinga configuration somewhat similar in appearance to that of housing 292 ofFIG. 31 with the exception that streamlined tip portion 346 ismonolithically formed with housing member 364. This embodiment isotherwise similar in operation to that of closed end housing member 354described above.

Referring to FIGS. 40 and 41, an open end housing member 366 is shownhaving a blade storage cavity 294 which is open at its distal end 368.Both upper and lower surfaces, 370, 372 are rounded to facilitate smoothinsertion into a cannula (not shown). As in the embodiment of FIGS. 36and 37, upper and lower surfaces 370, 372 of housing member 366 aresubstantially flattened near the distal end 368 and ramp out to conformin diameter and cross-section with guide tube 108. This embodiment isotherwise similar in operation to that of housing members 354 and 364above.

Turning now to FIG. 42, another embodiment 400 of the surgical retractorof the subject invention is illustrated. The surgical retractor 400comprises a handle portion 402 having opposed proximal and distal ends404 and 406, an elongated endoscopic portion 408 extending from thedistal end 406 of the handle portion 402, and a retractor assembly 410operatively associated with the distal end 412 of the endoscopic portion408. A rotator cuff 409 is provided on the endoscopic portion 408adjacent the distal end 406 of handle portion 402 for enabling a user torotate the endoscopic portion 408 about its longitudinal axis relativeto the handle portion 402. Retractor assembly 410 includes a pluralityof blade members including a center blade 4 14, an upper blade 416, anda lower blade 418. These retractor blades will be discussed in detailhereinbelow.

Referring to FIG. 43, the handle portion 402 of surgical retractor 400includes a two-part handle having hemi-sections 420 and 422. Whenassembled the hemi-sections 420 and 422 define a stepped axial bore 424which extends through the handle portion 402. The axial bore 424 has aproximal chamber 426, a medial chamber 428, and a distal chamber 430defined therein. A circumferential groove 432 is provided in the distalchamber 430. The handle portion 402 houses a driving assembly 434 whichmanipulates the retractor assembly 410.

Driving assembly 434 comprises a rotatable driving screw 436 and anaxially movable sleeve member 438. The driving screw 436 includes a tailportion 440, a slender body portion 442, and a threaded head portion444. The tail portion 440 is mounted within a receiving port 448 of aknob member 450 by a pair of screw type fasteners 452 and 454. The bodyportion 442 of the driving screw 436 is maintained within the proximalchamber 426 of the axial bore 424 of handle portion 422. The headportion 444 of driving screw 436 is threadably engaged to sleeve member438. More particularly, the sleeve member 438 is formed with a threadedinternal passage 456 which extends substantially along the lengththereof. In use, rotation of the driving screw 436 causes correspondingaxial translation of the sleeve member 438 relative to the handleportion 402 within the axial bore 424. The sleeve member 438 of drivingassembly 434 further includes a pair of diametrically opposed flanges458 and 460 which are dimensioned and configured for engagement incorresponding longitudinal tracks 462 and 464 provided in the medialchamber 428 of the axial bore 424 in handle portion 402. The opposedflanges 458 and 460 function to prohibit rotation of the sleeve member438 in response to operational rotation of driving screw 436. A notch462 is provided in the distal end of the sleeve member 438 and isadapted and configured for lockingly engaging the end of an elongatedrod member 466. Specifically, the proximal end 468 of rod member 466 isgenerally L-shaped and is configured so as to lockingly engage the notch462 in sleeve member 438. This connection between rod member 466 andsleeve member 438 functions substantially to translate the axialmovements of sleeve member 438 to the retractor assembly 410 which isarranged in the distal end 4 12 of endoscopic portion 408.

The endoscopic portion 408 of surgical retractor 400 has a proximal end470 at which a circumferential slot 472 is formed for maintaining aflange ring 474. A plug member 476, having an axial throughhole 478, anda rear flange 480 is mountable in the proximal end 470 of the endoscopicportion 408. Once the plug member 476 has been mounted in the proximalend 470 of endoscopic portion 408, the rear flange 480 functions tomaintain the flange ring 474 in the circumferential slot 472. Theendoscopic portion 408 is mounted in the distal chamber 430 of axialbore 424 in such a manner so that the flange ring 474 is maintainedwithin the circumferential groove 432. Additionally, an o-ring seal 475is disposed in the proximal end 470 of endoscopic portion 408 forprohibiting the egress of insufflation gas therethrough from the bodycavity. Similarly, an o-ring seal 477 is disposed in the distal end 4 12of endoscopic portion 408 for prohibiting the egress of insufflation gasfrom the surgical site. The proximal end 412 of endoscopic portion 408has diametrically opposed longitudinally extending slots 482 and 484which are provided for accommodating the operative deployments of theretractor assembly 410. An aperture 486 is formed adjacent the distalend 4 12 of endoscopic portion 408 for receiving a fastening member 488.Fastening member 488 is provided for fixing a coupling member 490 withinthe axially passage way 492 of the endoscopic portion 408 adjacent thedistal end 4 12 thereof. Coupling member 490 forms a base from which theretractor assembly 410 operates.

Referring to FIG. 43a, the coupling member 490 comprises a cylindricalbody section 492 and a rectangular platform section 494. The cylindricalbody section 492 has a diameter which is slightly less than that of theinner diameter of the endoscopic portion 408 of surgical retractor 400.A transverse aperture 496 extends through the body section 492 forreceiving fastener member 488 (FIG. 43). A longitudinal passage 498extends through body section 492 and platform section 494 foraccommodating the distal end 500 of rod member 466. The platform section494 is provided with a pair of spaced apart transverse mounting ports502 and 504 which extend therethrough for receiving a pair of set pins506 and 508, respectively. More particularly, the set pins 506 and 508mount upper and lower cam beams 510 and 512 to the platform section 494of coupling member 490.

Upper cam beam 510 has a pair of apertures 514 and 516 and lower cambeam 512 has a pair of apertures 518 and 520 which correspond to ports502 and 504 for receiving set pins 506 and 508. Upper can beam 510 isformed with a camming slot 522 which defines a path in which a camfollower 524 travels. Camming slot 522 includes a proximal portion 526which is disposed parallel to the longitudinal axis of cam beam 5 10 anda distal portion 528 which is disposed angularly with respect to theproximal portion 526 of camming slot 522. Similarly, the lower cam beam512 is formed with a camming slot 530 which a defines a path in whichcam follower 532 travels. Camming slot 530 includes a proximal portion534 which is disposed parallel to the longitudinal axis of cam beam 512and a distal portion 536 which is disposed angularly with respect to theproximal portion 526 of camming slot 522. The distal portion 536 ofcamming slot 522 and the distal portion 528 of camming slot 530 aresymmetrically disposed relative to one another so as to facilitate afan-like deployment configuration of the retractor assembly.

As stated briefly hereinabove, the retractor assembly 410 comprisesupper and lower retractor blades 416 and 418 and a center retractorblade 414. The center blade 414 includes an elongated body portion 538and a distal head portion 540 which depends angularly from the bodyportion 538 to define a paddle structure for increasing the retractingcapabilities of the instrument at a surgical site. A generally T-shapedgroove 542 is formed at the proximal end of the body portion 438 ofcenter blade 414. The T-shaped groove 542 is dimensioned and configuredfor engagement with a slotted head 544 formed at the distal end 500 ofrod member 466. (FIG. 43) An aperture 546 is provided forward from theT-shaped slot 542 for receiving a pivot pin 548.

The upper retractor blade 416 has a body portion 550 and a distal headportion 552 which depends angularly from the body portion 550,preferably at an angle of between 0° and 90°. An aperture 554 isprovided in the proximal end of the body portion 550 which correspondsto aperture 546 in center retractor blade 414 for receiving the pivotpin 548. In addition, a second aperture 556 is provided forward fromaperture 554, which is disposed adjacent a lateral edge 558 of blademember 416 for asymmetrically mounting cam follower 524. The upperretractor blade 416 can optionally include a bend 555 adjacent thedistal head portion 552 thereof to provide additional manipulation spacefor center retractor blade 4 14, as shown for example in FIG. 43a. Thelower retractor blade 418 has a body portion 560 and a distal headportion 562 which depends angularly from the body portion 560. Anaperture 564 is provided in the proximal end of body portion 560 whichcorresponds to aperture 546 in the center blade 4 14 for receiving pivotpin 548. In addition, a second aperture 566 is provided forward fromaperture 564, which is disposed adjacent a lateral edge 568 thereof forasymmetrically mounting cam follower 532. The retractor assembly 510further includes a pair of opposed stabilizer heads 570 and 572 whichare configured for engagement in passageway 492 of endoscopic portion408 at the distal end 4 12 thereof. Referring to FIG. 43a, each of theretractor blades of retractor assembly 410 may optionally include amolded plastic cover member 563 positioned at the distal head portionthereof to provide a more blunt tip for reducing trauma to tissue duringuse.

Turning now to FIGS. 44-46, in operation the retractor assembly 410 ofthe surgical retractor 400 can be deployed from a closed position byrotating knob member 450 in the direction of indicator arrow "A",relative to the handle portion 402. As the knob 450 is rotated, thedriving screw 436 rotates correspondingly. Rotation of the driving screw436 causes axial translation of the sleeve member 438 in the directionof indicator arrow "X" in FIG. 45. Consequently, rod member 466 movesdistally, urging the center retractor blade 414 of retractor assembly410 to travel in a distal direction. From a point in time of initialmovement of center blade 414, to an intermediate period of time whereinthe retractor assembly 410 is in a partially deployed position, asillustrated in FIG. 45, the blades 414,416, and 418 move as a unit, withthe longitudinal axes thereof substantially in parallel alignment. Thisinitial unitary-like movement of the retractor assembly 410 is achievedthrough the translation of the cam follower pins 524 and 532 within theproximal parallel portions of camming slots 522 and 530 respectively.

As rotation of the knob member 450 continues in the direction ofindicator arrow "A", the sleeve member 438 continues to travel in adistal direction within the distal chamber 428 defined in handle portion402. Accordingly, rod member 466, which is connected to sleeve member438 urges the center retractor blade 414 forward, further causing thecam follower pins 524 and 532 to continue to move in a generally distaldirection within camming slots 522 and 530, respectively. However, asthe cam follower pins 524 and 532 exit the proximal portions 526 and 536of camming slots 522 and 530, and enter the respective distal portions528 and 536 of camming slots 522 and 530, the upper blade 416 and lowerblade 418 of retractor assembly 410 begin to deploy outwardly in afan-like manner with respect to the center blade 414, pivotingsymmetrically about pin 548. The outward deployment of upper and lowerretractor blades 416 and 418 continues until the cam follower pins 524and 532 are in their distalmost positions within camming slots 522 and530, respectively.

Turning now to FIG. 47, the driving assembly 434 of surgical retractor400 can be provided with a position indicator mechanism consisting ofcooperating ratchet members 580 and 582. This mechanism produces adetectable indication to a user that the sleeve member 438 has reachedits distalmost or proximalmost position within the medial chamber 428 ofaxial bore 424. Ratchet member 580 defines a ring having a centerpassage 584 and a saw-toothed distal surface area 586. Diametricallyopposed flanges 588 and 590 extend from the periphery of ratchet member580 for maintaining ratchet member 580 within a first circumferentialchamber 592 formed in the distalmost chamber 426 of handle portion 402.Ratchet member 582 has an elongated body portion 594 which is engageablewithin the receiving port 448 of knob member 450. A circumferential headportion 595 is formed at the distal end of body portion 594 which has asaw-toothed surface 596 for cooperating with the saw teeth 586 onratchet member 580. An axial passage 597 extends through ratchet member582 for accommodating the driving screw 436 of driving assembly 434. Asecond circumferential groove 598 is provided in the handle portion 402adjacent circumferential groove 592 for accommodating the head portion595 of ratchet member 582.

Referring to FIG. 48, another embodiment of the surgical retractor ofthe subject invention is illustrated and is designated generally byreference numeral 600. Surgical retractor 600 comprises a handle portion602 having opposed proximal and distal ends 604 and 606, an elongatedendoscopic portion 608 which extends from the distal end 606 of handleportion 602, and a retractor assembly 610 operatively associated withthe distal end 612 of the endoscopic portion 608.

The handle portion 602 of the surgical retractor 600 includes a steppedaxial bore 614 which extends longitudinally therethrough from theproximal end 604 to the distal end 606 thereof. Axial bore 614 has aproximal chamber 616, a medial chamber 618, and a distal chamber 620defined therein. A driving assembly 622 is associated with handleportion 602 and is mounted within the axial bore 614 for operating theretractor assembly 610. Driving assembly 622 includes a knob member 624and a driving screw 626. Knob member 624 comprises a proximal graspingportion 628, a intermediate cavity portion 630 and a distal threadedportion 632. Knob member 624 is mountable within the axial bore 614 ofhandle portion 602 in such a manner so that the threaded portion 632thereof is maintained within the proximal chamber 616 of axial bore 614.Once mounted, knob member 624 is capable of rotating with respect to thelongitudinal axis of the handle portion 602. Driving screw member 626includes a threaded body portion 638, and a distal engaging portion 640.A transverse bore 642 is formed in the distal engaging portion 640,while a longitudinal bore 642 is also formed therein. Transverse bore642 is provided for maintaining a two-piece universal clip having afirst portion 646 and a second portion 648 which are adapted andconfigured for maintaining and engaging a grooved tail 650 at theproximal end 652 of rod member 654.

Driving member 626 is dimensioned and configured for mounting within theknob member 624 of handle portion 602. In particular, the threaded bodyportion 638 of driving member 626 is engageable with the threaded boreportion 632 of knob member 624. Rotations of knob member 624 duringoperations of retractor 600 cause corresponding axial movements ofdriving member 626 relative to the longitudinal axis of the handleportion 602. The medial chamber 618 has a diameter which is dimensionedto accommodate the axial translation of the threaded portion 638 ofdriving member 626 as it is driven in a distal direction within handleportion 602 in response to rotations of knob member 624.

The endoscopic portion 608 of surgical retractor 600 is mounted to thedistal end 606 of handle portion 602 by a plug member 650. Moreparticularly, plug member 650 includes a cylindrical body portion 652and a proximal circumferential flange portion 654. An axial passageway656 extends through the body portion 652 for permitting passage of thedistal end 658 of rod member 654. To mount the endoscopic portion 608 tohandle portion 602, the cylindrical body portion 652 of plug member 650is extended into the distal end 660 of endoscopic portion 608 in such amanner so that the flange portion 654 of plug member 650 abuts thedistal end 660 of endoscopic portion 608. The endoscopic portion 608 isthen mountable within the distal most chamber 620 of axial bore 614 ofhandle portion 602 and is maintained therein by flange portion 654 ofplug member 650 abutting against the wall 662 formed between medialchamber 618 and distal chamber 620. The distal end 612 of endoscopicportion 608 is provided with diametrically opposed longitudinallyextending slots 664 and 665 for accommodating the retractor assembly610.

The retractor assembly 610 of surgical retractor 600 includes a couplingmember 668 which has a proximal portion 670, a medial circumferentialgroove portion 672, and a slotted head portion 674 which has a pair ofdiametrically opposed platforms 676 and 678. An axial passage 680extends through the coupling member 668 for permitting extension of thedistal end 658 of rod member 654 therethrough. The lower platform 678 atthe head portion 674 of coupling member 668 includes spaced apartnotches 682 and 684, while the upper platform 676 includes spaced apartnotches 686 and 688. Set pins 690 and 692 are mountable within thesenotches formed in the opposed platforms 676 and 678. The coupling member668 is mountable within the axial bore 694 and is maintained therein bya crimp 696 formed in an area of the endoscopic portion 608 whichbecomes engaged in the circumferential groove 672 of coupling member 668once it has been mounted therein.

Retractor assembly 610 further includes upper and lower cam beams 698and 700. Upper cam beam 698 has a pair of spaced apart notches 702 and704 formed in a proximal end 706 thereof, for being engaged with the setpins 692 and 690, thus rigidly maintaining cam beam 698 relative to thecoupling member 668. Similarly, cam beam 700 includes a pair of spacedapart notches 708 and 710 provided adjacent the proximal end 712 thereofwhich are also provided for mounting with set pins 690 and 692, thusmaintaining cam beam 700 in a fixed position relative to coupling member668. A camming slot 714 is formed in upper cam beam 698 and defines apath within which a cam follower 716 translates. Camming slot 714 isdisposed angularly relative to the longitudinal axis of cam beam 698.Similarly, cam beam 700 is provided with a camming slot 718 finding apath within which a cam follower 720 translates. Camming slot 718 isdisposed angularly relative to the longitudinal axis of camming beam 700and is symmetrically disposed relative to the camming slot 714 of cambeam 698. The disposition of camming slots 714 and 718 facilitates thefan-like deployment of the retractor assembly 610.

The retractor assembly 610 of surgical retractor 600 further includes aplurality of retractor blade members which includes a center retractorblade 722, an upper retractor blade 724, and a retractor lower blade726. The center retractor blade 722 has an elongated body portion 728and a head portion 730 which depends angularly away from the bodyportion 728 to define a tong structure for increasing retractingcapabilities at the surgical site. A substantially I-shaped slot 732 isformed in the proximal end 734 of the center retractor blade 722. TheI-shaped slot is configured and adapted for engaging a grooved headportion 736 which is formed on the distal end 658 of rod member 654. Anaperture 736 is provided forwardly from the I-shaped slot 732 formounting a pivot pin 738.

The upper retractor blade 724 includes an elongated body portion 740 anda distal head portion 742 which depends angularly away from the bodyportion 740. An aperture 744 is provided in body portion 740 whichcorresponds to the pivot pin mounting aperture 736 in the centerretractor blade 722. In addition, an aperture 746 is provided in bodyportion 740 spaced from aperture 744 and disposed adjacent to a lateraledge 748 thereof. Aperture 746 is provided for mounting and maintainingthe cam follower 716. Lower retractor blade 726 includes a body portion750 and a distal head portion 752 which depends angularly from bodyportion 750 to define a tong like structure. An aperture 754 is providedin the body portion 750 which corresponds with the aperture 736 incenter retractor blade 722 and the aperture 746 in upper retractor blade724 for mounting the pivot pin 738. An additional aperture 756 isprovided in the body portion 750 of lower retractor blade 726 and isdisposed forward from aperture 754 and adjacent to a lateral edge 758thereof. Aperture 756 is provided for mounting and maintaining camfollower 720. The retractor assembly 610 further includes stabilizerheads 760 and 762 which are adapted and configured for mounting withinthe axially passageway 694 of endoscopic portion 608 adjacent the distalend 612 thereof.

Turning now to FIGS. 49-51, in operation the retractor assembly 610 ofsurgical instrument 600 can be deployed from a closed position byrotating the knob member 624 in the direction of indicator arrow "C",relative to the handle portion 602. As knob member 624 is rotated,driving screw 626 is caused to translate axially relative to the handleportion 602. Thereupon, the distal engaging portion 640 of driving screwmember 626 travels axially within the me, dial chamber 618 of handleportion 602. Accordingly, axial movement of driving screw 626 in adistal direction causes corresponding axial movements of rod member 654.Consequently, the center retractor blade 722 of retractor assembly 610is caused to travel in a distal direction. As center blade 722 moves ina distal direction with the longitudinal axis thereof maintainingparallel relationship with the longitudinal axis of the endoscopicportion 608, the upper and lower retractor blades 724 and 726 graduallydeploy outwardly with respect to the center blade 722, pivotingsymmetrically about pivot pin 738 upon distal movement. The outwarddeployment of the upper and lower retractor blades 724 and 726 iscontrolled by the translation of the cam followers 716 and 720 withintheir corresponding camming slots 714 and 718.

The surgical retractor of the present invention is a compact,lightweight and easy to use instrument incorporating many featuresrequired during endoscopic surgical procedures which allows the surgeonto use the instrument with one hand thus freeing the other hand formanipulation of other instruments during surgery. The present retractorovercomes many of the disadvantages encountered with prior art devicesand provides a precision instrument which is easy to handle and simpleto manufacture.

While the invention has been particularly shown and described withreference to preferred embodiments thereof, it will be understood bythose skilled in the art that various modifications in form and detailmay be made therein without departing from the scope and spirit of theinvention. Accordingly, modifications such as those suggested above, butnot limited thereto, are to be considered within the scope of theinvention.

What is claimed is:
 1. A surgical retractor comprising:actuation means;an endoscopic tubular portion extending from said actuation means; aretractor assembly associated with a distal end portion of said tubularportion and including a plurality of interleaved retractor bladespivotally connected to one another, each of said retractor blades havingan elongated planar body section and an atraumatic head sectiondepending arcuately from the plane of said body section, each headsection having a curved lateral profile and a curved leading edge; andmeans associated with said actuation means for manipulating saidplurality of retractor blades between a closed position and an openedposition.
 2. A surgical retractor as recited in claim 1, wherein saidhead section depends from said body section at an angle of about 45°. 3.A surgical retractor as recited in claim 1, wherein said plurality ofretractor blades includes a center blade, at least one upper blade, andat least one lower blade.
 4. A surgical retractor as recited in claim 3,wherein said retractor assembly further includes camming meansoperatively connected to said plurality of retractor blades.
 5. Asurgical retractor as recited in claim 4, wherein said camming meansincludes upper and lower cam beams fixedly mounted within said tubularportion adjacent the distal end thereof, said upper cam beam having anupper camming slot defined therein, and said lower cam beam having alower camming slot defined therein, said upper camming slot and saidlower camming slot being symmetrically disposed relative to one another,said at least one upper retractor blade including a cam follower formovement relative to said upper camming slot and said at least one lowerretractor blade including a cam follower for movement relative to saidlower camming slot.
 6. A surgical retractor as recited in claim 5,wherein said upper camming slot and said lower camming slot each have alongitudinal section and an angularly deviated section for defining apredetermined path of travel for each of said cam followers, saidpredetermined path enabling said plurality of retractor blades to travelinitially unitarily for a distance and thereafter enabling said at leastone upper blade and said at least one lower blade to deploy outwardlyrelative to said center blade.
 7. A surgical retractor as recited inclaim 3, wherein said retractor assembly further includes a rod memberadapted and configured for mounting at least one of said plurality ofretractor blades to said manipulating means.
 8. A surgical retractor asrecited in claim 7, wherein said manipulating means includes a drivingscrew mounted for rotation relative to said actuation means and a sleevemember threadably associated with said driving screw member fortranslating in an axial direction relative to a longitudinal axis ofsaid actuation means, in response to rotations of said driving screwmember.
 9. A surgical instrument as recited in claim 8, wherein said rodmember extends through said tubular portion for operatively connectingsaid sleeve member and said center blade in such a manner such thataxial movements of said sleeve member cause corresponding movements ofsaid plurality of retractor blades.
 10. A surgical retractor as recitedin claim 7, wherein said manipulating means includes a knob membermounted for rotation relative to said actuation means and a drivingscrew member threadably associated with said knob member for translatingin an axial direction relative to a longitudinal axis of said actuationmeans in response to rotations of said knob member.
 11. A surgicalretractor as recited in claim 10, wherein said rod member extendsthrough said tubular portion for operatively connecting said drivingscrew member and said center blade.
 12. A surgical retractor as recitedin claim 3, wherein said at least one upper blade and said at least onelower blade are symmetrically deployable in a fan-like configuration.13. A surgical retractor as recited in claim 1, wherein means areassociated with said manipulating means for indicating the position ofsaid retractor blades by producing an audible and tactile signal.
 14. Asurgical retractor as recited in claim 12, wherein means are associatedwith said tubular portion for rotating said tubular portion about thelongitudinal axis thereof relative to said actuation means.
 15. Asurgical retractor as recited in claim 1, wherein means are provided forsealing said tubular portion to prohibit the egress of insufflation gastherethrough.
 16. A surgical retractor comprising:actuation means; anendoscopic tubular portion extending from said actuation means; aretractor assembly associated with a distal end portion of said tubularportion and having a plurality of retractor blades including at leastone upper retractor blade and at least one lower retractor bladepivotally connected to one another; camming means operatively connectedto said retractor blades including upper and lower cam beams fixedlymounted within said tubular portion adjacent said distal end portionthereof with said upper cam beam having an upper camming slot definedtherein and said lower cam beam having a lower camming slot definedtherein, said at least one upper retractor blade having an upper camfollower mounted for movement relative to said upper camming slot andsaid at least one lower retractor blade having a lower cam followermounted for movement relative to said lower camming slot; andmanipulating means associated with said actuation means for moving saidupper and lower cam followers relative to said upper and lower cammingslots to move said retractor blades between a closed position and anopened position.
 17. A surgical retractor comprising:actuation means; anendoscopic tubular portion extending from said actuation means; aretractor assembly associated with a distal end portion of said tubularportion and including a plurality of interleaved retractor bladespivotally connected to one another, each of said retractor blades havingan elongated planar body section and an atraumatic head sectiondepending from the plane of said body section; means associated withsaid actuation means for manipulating said plurality of retractor bladesbetween a closed position and an opened position; and a ratchetmechanism mounted for rotation relative to said actuation means forindicating the position of said retractor blades by producing an audibleand tactile signal.
 18. A surgical retractor comprising:a) handle meansincluding manipulation structure; b) an endoscopic portion extendingfrom said handle means; c) a retractor assembly associated with a distalend portion of said endoscopic portion and including:i) a plurality ofinterleaved retractor blades pivotally connected to one anotherincluding a center blade, at least one upper blade, and at least onelower blade; ii) a camming assembly associated with said plurality ofretractor blades including a base, an upper cam beam extending from saidbase cooperative with said at least one upper retractor blade, and alower cam beam extending from said base cooperative with said at leastone lower retractor blade; and d) means for connecting said manipulationstructure and said center blade.
 19. A surgical retractor as recited inclaim 18, wherein said manipulation structure comprises a driving screwmounted for rotation relative to said handle means and a threaded sleevemember connected to said driving screw for moving axially, relative to alongitudinal axis of said handle means, in response to rotation of saiddriving screw.
 20. A surgical retractor as recited in claim 19, whereinsaid means for connecting said manipulation structure and said centerblade is an elongated rod extending from said sleeve member.
 21. Asurgical retractor as recited in claim 19, wherein said means forconnecting said manipulation structure and said center blade is anelongated rod extending from said driving screw.
 22. A surgicalretractor as recited in claim 18, wherein said manipulation structurecomprises a threaded knob member mounted for rotation relative to saidhandle means and a driving screw connected to said knob member formoving axially, relative to a longitudinal axis of said handle means, inresponse to rotations of said knob member.
 23. A surgical retractor asrecited in claim 18, wherein each of said retractor blades includes aplanar body portion and a head portion depending angularly from theplane of said body portion.
 24. A surgical retractor as recited in claim18, wherein said upper cam beam and said lower cam beam each include acamming slot defining a path within which a cam follower translates. 25.A surgical retractor as recited in claim 24, wherein each of saidcamming slots include a proximal section extending parallel to alongitudinal axis of a respective one of said cam beams and a distalsection extending angularly from said proximal section for defining apath of travel for each of said cam followers, said predetermined pathenabling said plurality of retractor blades to travel initiallyunitarily for a distance and thereafter enabling said at least one upperblade and said at least one lower blade to deploy outwardly relative tosaid center blade.
 26. A surgical retractor as recited in claim 25,wherein the distal portion of the camming slot in said upper cam beam issymmetrically oriented relative to the distal portion of the cammingslot in said lower cam beam for enabling a fan-like deployment of saidretractor blades.
 27. A surgical retractor as recited in claim 18,wherein means are provided for sealing said endoscopic portion toprohibit the egress of insufflation gas therethrough.
 28. A surgicalretractor as recited in claim 18, wherein means are associated with saidendoscopic portion for rotating said endoscopic portion about thelongitudinal axis thereof relative to said handle means.
 29. A surgicalretractor as recited in claim 18, wherein means are associated with saidmanipulating means for indicating the position of said retractor bladesby audible and tactile signal.